System and method for carrying a wireless based signal over wiring

ABSTRACT

A device, network and method wherein a standard wireless modem is coupled to wiring for carrying a wireless baseband signal that may be OFDM based, and may be directly generated by the wireless IF modem, or extracted from the modem RF signal. The wiring may be a building utility wiring, such as telephone, AC power or CATV wiring. The baseband signal is carried simultaneously with the utility service signal over the utility wiring using Frequency Division Multiplexing. The device may be enclosed with a data unit, a standalone dedicated enclosure, within an outlet or as a plug-in outlet adapter. Data units may couple the device by a wiring port such as standard data connector, or via wireless connection. The device may be locally powered or via a power signal carried over the wiring. This abstract is not intended to limit or construe the scope of the claims.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/129,278 filed 29 May 2008, which is a continuation of U.S. patentapplication Ser. No. 11/066,442 filed 28 Feb. 2005, now abandoned claimsany and all benefits of the prior filed applications as provided by lawand the contents of each of the earlier filed applications are herebyincorporated by reference in its entirety.

This application is related to U.S. application Ser. No. 11/329,270,filed on 11 Jan. 2006 and 12/038,435, filed on 27 Feb. 2008.

FIELD OF THE INVENTION

The present invention relates to the field of wired communication, and,more specifically, to using wireless oriented signals over a wiredmedium.

BACKGROUND OF THE INVENTION

Wired Home Networking.

Most existing offices and some of the newly built buildings facilitate adata network structure based on dedicated wiring. However, implementingsuch a network in existing buildings typically requires installation ofnew wiring infrastructure. Such installation of new wiring may beimpractical, expensive and problematic. As a result, many technologies(referred to as “no new wires” technologies) have been proposed in orderto facilitate a LAN in a building without adding new wiring. Some ofthese techniques use existing utility wiring installed primarily forother purposes such as telephone, electricity, cable television (CATV),and so forth. Such an approach offers the advantage of being able toinstall such systems and networks without the additional and oftensubstantial cost of installing separate wiring within the building.

The technical aspect for allowing the wiring to carry both the service(such as telephony, electricity and CATV) and the data communicationsignal commonly involves using FDM technique (Frequency DivisionMultiplexing). In such configuration, the service signal and the datacommunication signals are carried across the respective utility wiringeach using a distinct frequency spectrum band. The concept of FDM isknown in the art, and provides means of splitting the bandwidth carriedby a medium such as wiring. In the case of a telephone wiring carryingboth telephony and data communication signals, the frequency spectrum issplit into a low-frequency band capable of carrying an analog telephonysignal and a high-frequency band capable of carrying data communicationor other signals.

A network in a house based on using powerline-based home network is alsoknown in the art. The medium for networking is the in-house power lines,which is used for carrying both the mains power and the datacommunication signals. A PLC (Power Line Carrier) modem converts a datacommunication signal (such as Ethernet IEEE802.3) to a signal which canbe carried over the power lines, without affecting and being affected bythe power signal available over those wires. A consortium named HomePlugPowerline Alliance, Inc. of San Ramon, Calif. USA is active instandardizing powerline technologies. A powerline communication systemis described in U.S. Pat. No. 6,243,571 to Bullock et al., which alsoprovides a comprehensive list of prior art publications referring topowerline technology and application. An example of such PLC modemhoused as a snap-on module is HomePlug1.0 based Ethernet-to-PowerlineBridge model DHP-100 from D-Link® Systems, Inc. of Irvine, Calif., USA.Outlets with built in PLC modems for use with combined data and powerusing powerlines are described in US Patent Application 2003/0062990 toSchaeffer et al. entitled ‘Powerline bridge apparatus’. Such poweroutlets are available as part of PlugLAN™ by Asoka USA Corporation ofSan Carlos, Calif. USA.

Similarly, carrying data over existing in home CATV coaxial cabling isalso known in the art, for example in US Patent application 2002/0166124to Gurantz et al. An example of home networking over CATV coaxial cablesusing outlets is described in US Patent application 2002/0194383 toCohen et al. Such outlets are available as part of HomeRAN™ system fromTMT Ltd. of Jerusalem, Israel.

Telephony Definitions and Background

The term “telephony” herein denotes in general any kind of telephoneservice, including analog and digital service, such as IntegratedServices Digital Network (ISDN).

Analog telephony, popularly known as “Plain Old Telephone Service”(“POTS”) has been in existence for over 100 years, and is well-designedand well-engineered for the transmission and switching of voice signalsin the 300-3400 Hz portion (or “voice band” or “telephone band”) of theaudio spectrum. The familiar POTS network supports real-time,low-latency, high-reliability, moderate-fidelity voice telephony, and iscapable of establishing a session between two end-points, each using ananalog telephone set.

The terms “telephone”, “telephone set”, and “telephone device” hereindenote any apparatus, without limitation, which can connect to a PublicSwitch Telephone Network (“PSTN”), including apparatus for both analogand digital telephony, non-limiting examples of which are analogtelephones, digital telephones, facsimile (“fax”) machines, automatictelephone answering machines, voice (a.k.a. dial-up) modems, and datamodems.

The terms “data unit”, “computer” and “personal computer” (“PC”) areused herein interchangeably to include workstations, Personal DigitalAssistants (PDA) and other data terminal equipment (DTE) with interfacesfor connection to a local area network, as well as any other functionalunit of a data station that serves as a data source or a data sink (orboth).

In-home telephone service usually employs two or four wires, to whichtelephone sets are connected via telephone outlets.

Home Networking Existing in-House Wiring.

Similarly to the powerlines and CATV cabling described above, it isoften desirable to use existing telephone wiring simultaneously for bothtelephony and data networking. In this way, establishing a new localarea network in a home or other building is simplified, because there isno need to install additional wiring. Using FDM technique to carry videoover active residential telephone wiring is disclosed by U.S. Pat. No.5,010,399 to Goodman et al. and U.S. Pat. No. 5,621,455 to Rogers et al.

Existing products for carrying data digitally over residential telephonewiring concurrently with active telephone service by using FDM commonlyuses a technology known as HomePNA (Home Phoneline Networking Alliance)whose phonelines interface has been standardized as ITU-T (ITUTelecommunication Standardization Sector) recommendation G.989.1. TheHomePNA technology is described in U.S. Pat. No. 6,069,899 to Foley,U.S. Pat. No. 5,896,443 to Dichter, U.S. Patent application 2002/0019966to Yagil et al., U.S. Patent application 2003/0139151 to Lifshitz et al.and others. The available bandwidth over the wiring is split into alow-frequency band capable of carrying an analog telephony signal(POTS), and a high-frequency band is allocated for carrying datacommunication signals. In such FDM based configuration, telephony is notaffected, while a data communication capability is provided overexisting telephone wiring within a home.

Prior art technologies for using the in-place telephone wiring for datanetworking are based on single carrier modulation techniques, such as AM(Amplitude Modulation), FM (Frequency Modulation) and PM (PhaseModulation), as well as bit encoding techniques such as QAM (QuadratureAmplitude Modulation) and QPSK (Quadrature Phase Shift Keying) and CCK(Complementary Code Keying). Spread spectrum technologies, to includeboth DSSS (Direct Sequence Spread Spectrum) and FHSS (Frequency HoppingSpread Spectrum) are known in the art. Spread spectrum commonly employsMulti-Carrier Modulation (MCM) such as OFDM (Orthogonal FrequencyDivision Multiplexing). OFDM and other spread spectrum are commonly usedin wireless communication systems, and in particular in WLAN networks.As explained in the document entitled “IEEE 802.11g Offers Higher DataRates and Longer Range” to Jim Zyren et al. by Intersil which isincorporated herein by reference, multi-carrier modulation (such asOFDM) is employed in such wireless systems in order to overcome thesignal impairment due to multipath. Since OFDM as well as other spreadspectrum technologies are considered to be complex and expensive(requiring Digital Signal Processors—DSP), and since telephone wiring isconsidered a better communication medium wherein multipath is lessconsidered as a major impairment than it is in wireless networks, OFDMtechnique (and any other spread spectrum or any multi-carriermodulation), which is considered to be powerful and high performance,has not been suggested as a dominant modulation for wired communicationin general and over telephone wiring in particular.

There is thus a widely recognized need for, and it would be highlyadvantageous to have a method and system for using spread spectrum modemtechnologies such as OFDM for wired applications, such as over utilitywiring, and in particular over telephone wiring.

Wireless Home Networking.

A popular approach to home networking (as well as office and enterpriseenvironments) is communication via radio frequency (RF) distributionsystem that transports RF signals throughout a building to and from datadevices. Commonly referred to as Wireless Local Area Network (WLAN),such communication makes use of the Industrial, Scientific and Medical(ISM) frequency spectrum, which is unregulated and license free. In theUS, three of the bands within the ISM spectrum are the A band, 902-928MHz; the B band, 2.4-2.484 GHz (a.k.a. 2.4 GHz); and the C band,5.725-5.875 GHz (a.k.a. 5 GHz). Overlapping and/or similar bands areused in different regions such as Europe and Japan.

In order to allow interoperability between equipments manufactured bydifferent vendors, few WLAN standards have evolved, as part of theInstitute of Electrical and Electronic Engineers (IEEE) 802.11 standardgroup, branded as WiFi Error! Hyperlink reference not valid. the Wi-FiAlliance of Austin, Tex., USA. IEEE 802.11b describes a communicationusing the 2.4 GHz frequency band and supporting communication rate of 11Mb/s, IEEE 802.11a uses the 5 GHz frequency band to carry 54 MB/s andIEEE 802.11g uses the 2.4 GHz band to support 54 Mb/s. This is describedin an Intel White Paper entitled “54 Mbps IEEE 802.11 Wireless LAN at2.4 GHz”, and a chip-set is described in an Agere Systems White Paperentitled “802.11 Wireless Chip Set Technology White Paper”, both ofthese documents being incorporated herein by reference.

A node/client with a WLAN interface is commonly referred to as STA(Wireless Station/Wireless client). The STA functionality may beembedded as part of the data unit, or alternatively may be a dedicatedunit, referred to as bridge, coupled to the data unit. While STAs maycommunicate without any additional hardware (ad-hoc mode), such networkusually involves Wireless Access Point (a.k.a. WAP or AP) as a mediationdevice. The WAP implements the Basic Stations Set (BSS) and/or ad-hocmode based on Independent BSS (IBSS). STA, client, bridge and WAP willbe collectively referred to herein as WLAN unit.

Bandwidth allocation for IEEE802.11g wireless in the USA is shown asgraph 20 in FIG. 2, along the frequency axis 27. In order to allowmultiple communication sessions to take place simultaneously, elevenoverlapping channels are defined spaced 5 MHz apart, spanning from 2412MHz as the center frequency for channel number 1 (shown as 23), viachannel 2 centered at 2417 MHz (shown as 24) and 2457 MHz as the centerfrequency for channel number 10 (shown as 25), up to channel 11 centeredat 2462 MHz (shown as 26). Each channel bandwidth is 22 MHz,symmetrically (±11 MHz) located around the center frequency.

WLAN unit block diagram 10 is shown in FIG. 1. For the sake ofsimplicity, only IEEE802.11g will be described from now on. In general,the wireless physical layer signal is handled in two stages. In thetransmission path, first the baseband signal (IF) is generated based onthe data to be transmitted, using 256 QAM (Quadrature AmplitudeModulation) based OFDM (Orthogonal Frequency Division Multiplexing)modulation technique, resulting in a 22 MHz (single channel wide)frequency band signal. The signal is then up converted to the 2.4 GHz(RF) and placed in the center frequency of the required channel, andwirelessly transmitted via the antenna. Similarly, the receiving pathcomprises a received channel in the RF spectrum, down converted to thebaseband (IF) from which the data is then extracted.

The WLAN unit 10 connects to the wired medium via port 11, supporting anIEEE802.3 10/100BaseT (Ethernet) interface. The physical layer of thisinterface is handled by a 10/100BaseT PHY function block 12, convertingthe incoming Manchester or MLT3 modulated signal (according to the10BaseT or 100BaseTX coding, respectively) into a serial digital stream.Similarly, a WLAN outgoing digital data stream is modulated to therespective coded signal and transmitted via the port 11, implementingfull duplex communication. The internal digital stream may be ofproprietary nature of any standard such as MII (Media IndependentInterface). Such MII to Ethernet PHY 12 (a.k.a. Ethernet physical layeror Ethernet transceiver) can be implemented based on LAN83C180 10/100Fast Ethernet PHY Transceiver available from SMSC—Standard MicrosystemsCorporation of Hauppauge, N.Y. U.S.A. While this function can beimplemented by using a single dedicated component, in many embodimentsthis function is integrated into single component including otherfunctions, such as handling higher layers. The PHY block 12 alsocomprises the isolation magnetics, balancing, surge protection andconnector (commonly RJ-45) required for proper and standard interfacevia port 11.

For the sake of simplicity, in the foregoing and subsequent descriptiononly Ethernet 10/100BaseT interface will be described. However, it willbe appreciated that any wired interface, being proprietary or standard,packet or synchronous, serial or parallel may be equally used, such asIEEE1394, USB, PCI, PCMCIA or IEEE1284. Furthermore, multiple suchinterfaces (being of the same type or mixed) may also be used.

In the case wherein the WLAN unit is integrated and enclosed withinanother unit (such as data unit, e.g. computer) and does not support adedicated and direct wired interface, the function of block 12 may beomitted.

MAC (Media Access Control) and higher layers are handled in functionblock 13, comprising two sub blocks, designated as 10/100BaseT MAC block13 a and IEEE802.11g MAC block 13 b (typically, the same MAC device isused for all IEEE802.11 variants, such as a/b/g). The MAC block 13 ahandles the MAC layer according to IEEE802.3 MAC associated with thewired port 11. Such a function block 13 a may be implemented usingLAN91C111 10/100 Non-PCI Ethernet Single Chip MAC+PHY available fromSMSC—Standard Microsystems Corporation of Hauppauge, N.Y. U.S.A, whichincludes both the MAC 13 a and the PHY 12 functionalities. Reference ismade to the manufacturer's data sheet: SMSC—Standard MicrosystemsCorporation, LAN91C111 10/100 Non-PCI Ethernet Single Chip MAC+PHY,Datasheet Rev. 15 (Feb. 20, 2004), which is incorporated herein byreference. Similarly, the MAC block 13 b handles the MAC layer accordingto IEEE802.11g MAC associated with the wireless port 22. Such MAC 13 bis designed to support multiple data rates, encryption algorithms and iscommonly based on an embedded processor and various memories. Such afunctional block 13 b may be implemented using WaveLAN™ WL60040Multimode Wireless LAN media Access Controller (MAC) from Agere Systemsof Allentown, Pa. U.S.A., whose a product brief is incorporated hereinby reference, which is part of a full chip-set as described in WaveLAN™802.11a/b/g Chip Set document from Agere Systems of Allentown, Pa.U.S.A., which is incorporated herein by reference. Reference is made tothe manufacturer's data sheet Agere Systems, WaveLAN™ WL60040 MultimodeWireless LAN Media Access Controller (MAC), Product Brief August 2003PB03-164WLAN, which is incorporated herein by reference. All thebridging required in order to connect the wired IEEE802.3 MAC handled byblock 13 a to the wireless IEEE802.11g MAC handled by block 13 b is alsoincluded in functional block 13, allowing for integrated and properoperation.

The data stream generated by the IEEE802.11g MAC 13 b is converted to anOFDM-based baseband signal (and vice versa) by the baseband processor18. In common applications, the baseband processor 18 (a.k.a. wirelessmodem and IF transceiver) is implemented by a transmitter/receiver 14digitally processing the data stream, and an analog unit (I-Q modulator)15 generating the actual signal. The communication channel in wirelessenvironments imposes various impairments such as attenuation, fading,multi-path, interferences among others, and the transmitter may processthe data stream according to the following functions:

-   -   a. Packet framing, wherein the data from the MAC 13 is adapted        and organized as packets, wherein header, CRC, preamble, control        information and end-of-frame delimiter are added.    -   b. Scrambler.    -   c. Convolution encoder (such as Viterbi encoder) to allow better        robustness against channel impairments such as impulse and burst        noise.    -   d. Puncturer to reduce the required data rate.    -   e. Interleaver performing permutations on the packet blocks        (e.g. bytes) in order to better immune against error bursts by        spreading the information.    -   f. IFFT modulator to produce separate QAM (quadrature Amplitude        Modulation) constellation sub-carriers.

Using digital to analog conversion, the processed digital from thetransmitter 14 is used to generate the OFDM baseband signal in themodulator 15. The received OFDM baseband signal from functional block 16is digitized by the modulator 15, processed by the receiver 14,transferred to MAC 13 and PHY 12 to be conveyed via port 11. Someimplementations of WLAN chipsets provide the actual baseband signal,while others provides orthogonal analog I/Q modem signals which need tobe further processed to provide the actual real analog form IF(Intermediate Frequency) OFDM baseband signal. In such a case, as knownin the art, a Local Oscillator (LO) determining the IF frequency is usedto generate a sine wave which is multiplied by the I signal, added tothe Q signal multiplied by 90 degrees shifted LO signal, to produce thereal analog IF baseband signal. Such function can be implemented basedon Maxim MAX2450 3V, Ultra-Low-Power Quadrature Modulator/Demodulatorfrom Maxim Integrated Products of Sunnyvale, Calif. U.S.A, a data sheetof which is incorporated herein by reference. The baseband processorblock 18 may be implemented based on WaveLAN™ WL64040 Multimode WirelessLAN Baseband from Agere Systems of Allentown, Pa. U.S.A., whose productbrief is incorporated herein by reference. SA5250 Multi-ProtocolBaseband from Philips Semiconductors including both baseband processor18 and MAC 13 b functionalities may be alternatively used.

The RF-IF Converter functional block 16 shifts the IF OFDM basebandsignal from the IF band to the ISM RF band. For example, an OFDMbaseband signal symmetrically centered around 10 MHz and required to usechannel 2 centered at 2417 MHz, is required to be frequency shifted by2417−10=2407 MHz. Such frequency conversion may use many methods knownin the art. A direct modulation transmitter/receiver may be used, suchas WaveLAN™ WL54040 Dual-Band Wireless LAN Transceiver from AgereSystems of Allentown, Pa. U.S.A., for directly converting the orthogonalI-Q analog signal to the 2.4 GHz RF band. A product brief isincorporated herein by reference. Alternatively, superheterodyne (dualconversion, for example) architecture may be used, as described forSA5251 Multiband RF Transceiver from Philips Semiconductors. Theconverter 16 and the baseband processor 18 constitute the wireless pathphysical layer processor 17.

A T/R switch 19 is used to connect the antenna 22 to the transmitterpath and disconnect the receiver path (to avoid receiver saturation)only upon a control signal signaling transmission state of the WLAN unit10. PIN Diode switch based design is commonly used, such as PIN Diodeswitch SWX-05 from MCE-KDI Integrated Products of Whippany, N.J. U.S.A.,whose data sheet is incorporated herein by reference. The antenna 22 iscoupled via a RF filter 21 in order to ensure transmitting limited tothe defined band mask (removing unwanted residual signals), and tofilter out noise and out of band signal in the receiving mode. Such RFfilter 21 may use SAW (Surface Acoustic wave) technology, such as 2441.8MHz SAW Filter from SAWTEK (A TriQuint company) of Orlando, Fla. U.S.A.,whose data sheet is incorporated herein by reference.

Actual implementation of the WLAN unit 10 may also involve amplifiers,attenuators, limiters, AGC (Automatic Gain Control) and similar circuitsinvolved with signal level functions. For example, a Low Noise Amplifier(LNA), such as MAX2644 2.4 GHz SiGe, High IP3 Low-Noise Amplifier iscommonly connected in the receive path near the antenna 22. Similarly, aPower Amplifier (PA) is used in the transmit path, such as MAX2247 PowerAmplifier for IEEE802.11g WLAN. Both the LNA and the PA are availablefrom Maxim Integrated Products of Sunnyvale, Calif. U.S.A. For the sakeof simplicity, such functions are omitted in FIG. 1 as well as in therest of this document. Similarly, wherever either a transmitting or areceiving path is described in this document, it should be understoodthat the opposite path also exists for configuring the reciprocal path.

Outlets

The term “outlet” herein denotes an electro-mechanical device, whichfacilitates easy, rapid connection and disconnection of external devicesto and from wiring installed within a building. An outlet commonly has afixed connection to the wiring, and permits the easy connection ofexternal devices as desired, commonly by means of an integratedconnector in a faceplate. The outlet is normally mechanically attachedto, or mounted in, a wall or similar surface. Non-limiting examples ofcommon outlets include: telephone outlets for connecting telephones andrelated devices; CATV outlets for connecting television sets, VCR's, andthe like; outlets used as part of LAN wiring (a.k.a. structured wiring)and electrical outlets for connecting power to electrical appliances.The term “wall” herein denotes any interior or exterior surface of abuilding, including, but not limited to, ceilings and floors, inaddition to vertical walls.

Wireless Coverage.

Most existing wireless technologies such as IEEE802.11x (e.g.IEEE802.11a/g/b), BlueTooth™, UWB (Ultra WideBand) and others arelimited to tens of meters in free line of sight environment. In commonbuilding environments, wherein walls and other obstacles are present,the range may be dramatically reduced. As such, in most cases a singlewireless unit (such as an access point) cannot efficiently cover thewhole premises. In order to improve the coverage, multiple access points(or any other WLAN units) are commonly used, distributed throughout thepremises.

In order to allow the access points to interconnect in order to form asingle communication cluster in which all the WLAN units can communicatewith each other and/or with wired data units, a wired backbone iscommonly used, to which the access points are connected. Such a networkcombining wired and wireless segments is disclosed for example in U.S.Pat. No. 6,330,244 to Swartz et al. Such a configuration is populartoday in offices, businesses, enterprises, industrial facilities andother premises having a dedicated wiring network structure, commonlybased on Category 5 cabling (a.k.a. structured wiring). The accesspoints interface the existing wiring based on local area network (LAN),commonly by a standard data interface such as Ethernet based10/100BaseT.

However, installing a dedicated network wiring infrastructure inexisting houses is not practical as explained above. The prior artdiscloses using existing AC power wiring also as the wired backbone forinterconnecting WLAN units. Examples of such prior art includes U.S.Pat. No. 6,535,110 to Arora et al., U.S. Pat. No. 6,492,897 to Mowery,Jr., U.S. Patent application 2003/0224728 to Heinonen et al., U.S. Pat.No. 6,653,932 to Beamish et al. Using powerlines as a backbone forconnecting WLAN units involves several drawbacks. The type of wiring,noise and the general hostile environment results in a poor andunreliable communication medium, providing low data rates and requiringcomplex and expensive modems. In addition, the connection of a WLAN unitto the powerline requires both wireless and powerline modems forhandling the physical layer over the two media involved, as well as acomplex MAC (Media Access control) to bridge and handle the two distinctprotocols involved. As such, this solution is complex, expensive andoffers low reliability due to the amount of hardware required.

There is thus a widely recognized need for, and it would be highlyadvantageous to have a method and system for using wireless modemtechnologies and components in a wired applications. Furthermore, itwould be highly advantageous to have a method and system for costeffectively enlarging the coverage of a wireless network by carrying awireless signal over a wired medium without converting to a dedicatedwired modem signal.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a method andsystem for using standard existing wireless components for wiredcommunication.

According to the invention, a standard wireless baseband signal that isconducted by existing wireless components (widely used for wirelesstransmission), is coupled and carried by a wiring, as a substitute for adedicated wiring modem. As such, a network (such as local area network)can be configured over the wiring, either in bus topology,point-to-point or any other arbitrary network topology. The invention isbased on a WLAN unit design, comprising a wired data port and a wirelessport (e.g. antenna) and enabling a data unit connected to the wired dataport (either proprietary or standard) to wirelessly communicate withother data unit.

In one aspect of the present invention, a device is based on a WLAN datadesign. However, only the baseband signal is used, so that the basebandto RF portion (hereinafter ‘RF portion’) of the WLAN unit may beobviated. The baseband signal may be coupled to the wiring viaisolation, analog switching, driver and receiver, filtering andimpedance matching functionalities, allowing for networking over thewiring with one or more similar devices coupled thereto.

In another aspect of the present invention, the RF portion of the WLANunit is also used. In this case, an up/down converter is connected tothe RF port (instead of connecting antenna thereto). The convertershifts the center frequency down to a band usable over the wiring.

In another aspect of the present invention, the full functionality ofthe WLAN unit is retained, including both the antenna and the RFportion. A wiring port coupled either directly to the baseband signal orto the RF signal via an up/down converter is added. In this case, athree ports sharing device is formed, having a wiring port, wireless(antenna) port and data unit port. Data units connected to a networkcomprising such multiple devices may be interconnected by the wiredmedium (via the wiring) or via the air using the RF signals propagatingthrough the air.

In another aspect of the present invention, the device comprises onlythe RF portion of a WLAN unit (including antenna). The antenna RF signalis frequency shifted by an up/down converter to a frequency band usableby the wiring (e.g. baseband signal). A similar device or a deviceaccording to any of the above embodiments connected to the wiring maycouple to the signal, and use it for coupling to a data unit eitherdirectly or wirelessly.

Any single pair wiring may be used as a medium for the baseband signal.In another aspect of the present invention, the wiring is utility wiringin a building, such as telephone, CATV or AC power wiring. In the casewherein the utility wiring also carries an active service signal (e.g.telephone, CATV or AC power signal respectively), FDM technique is used,wherein the service signal and the baseband signal are carried indistinct frequency bands. In another aspect of the present invention,the device further provides a service connector allowing a service unitto be connected thereto. In any case of wiring carrying active servicesignal, various filters are employed in order to isolate the servicesignal from the baseband signal, to avoid any interference between thetwo signals.

In another aspect of the present invention, the device may be comprisedin a data unit. Alternatively, the device may be enclosed as astand-alone dedicated unit. In another aspect of the present invention,the device is comprised within a service outlet. Alternatively, thedevice may be enclosed as outlet add-on module.

The device may be locally powered by a dedicated connection to a localpower source (e.g. AC power, directly or via AC/DC converter).Alternatively, the device is power fed from a power signal carried overthe wiring. In the latter case, a circuitry isolating the power signalcarried over the wiring is employed. In another aspect of the presentinvention, the device is powered by a data unit connected thereto.

In another aspect of the present invention, spread spectrum (either DSSSor FHSS) techniques such as employing a multi-carrier modulation (e.g.OFDM, DMT or CDMA) modem, which due to its complexity is mainly used forwireless applications, may be used over a wired medium such as utilitywiring in a building (e.g. telephone wiring).

It is understood that other embodiments of the present invention willbecome readily apparent to those skilled in the art from the followingdetailed description, wherein are shown and described only embodimentsof the invention by way of illustration. As will be realized, theinvention is capable of other and different embodiments and its severaldetails are capable of modification in various other respects, allwithout departing from the scope of the present invention as defined bythe claims. Accordingly, the drawings and detailed description are to beregarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of non-limiting example only,with reference to the accompanying drawings, wherein:

FIG. 1 shows schematically a general functional block diagram of a priorart WLAN unit.

FIG. 2 shows schematically the frequency spectrum allocation ofIEEE802.11g standard.

FIG. 3 shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 4 shows schematically the frequency spectrum allocation over thetelephone wiring according to the invention.

FIG. 5 shows schematically a general functional block diagram of anexemplary up/down converter according to the invention.

FIG. 6 shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 6 a shows schematically a general functional block diagram of anexemplary line interface according to the invention.

FIG. 6 b shows schematically a general functional block diagram of anexemplary network according to the invention.

FIG. 7 shows schematically a general functional block diagram of anexemplary network according to the invention.

FIG. 8 shows schematically a view of an exemplary telephone outletaccording to the invention.

FIG. 9 shows schematically a view of an exemplary telephone moduleaccording to the invention.

FIG. 10 shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 10 a shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 11 shows schematically a view of an exemplary telephone moduleaccording to the invention.

FIG. 12 shows schematically a general functional block diagram of anexemplary network according to the invention.

FIG. 13 shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 14 shows schematically a general functional block diagram of anexemplary network according to the invention.

FIG. 15 shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 16 shows schematically a general functional block diagram of anexemplary OFDM modem according to the invention.

FIG. 17 shows schematically a general functional block diagram of anexemplary network according to the invention.

DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

The principles and operation of a network according to the presentinvention may be understood with reference to the drawings and theaccompanying description wherein similar components appearing indifferent figures are denoted by identical reference numerals. Thedrawings and descriptions are conceptual only. In actual practice, asingle component can implement one or more functions; alternatively,each function can be implemented by a plurality of components andcircuits. In the drawings and descriptions, identical reference numeralsindicate those components that are common to different embodiments orconfigurations.

A wireless based OFDM modem 30 adapted for operating over telephonewiring according to one or more embodiments of the present invention isdescribed in FIG. 3. OFDM modem 30 is primarily based on the design andcomponents shown as WLAN unit 10 in FIG. 1. In contrast to WLAN unit 10,the RF signal is not coupled to antenna 22, but rather connect to anup/down converter 31. The converter 31 shifts the ISM band basebandsignal to a band usable over telephone wiring in home/office or anyother building. Owing to FCC regulation in North America regardingradiated electromagnetic emission, the usable frequency band isconsidered to extend up to 30 MHz. Hence, a spectrum allocation for abaseband signal occupying 22 MHz may be between 8 MHz and 30 MHz(centered around 19 MHz), as shown in curve 43 being part of graph 40 inFIG. 4, illustrating the various power levels allocation along thefrequency axis 44. Such allocation allows for ADSL signal 42 using the100 KHz (or 25 KHz) to 1.1 MHz and the POTS signal curve 41. ADSL is anacronym for Asymmetric Digital Subscriber Line uses standard phone linesto deliver high-speed data communications both upstream and downstream,using a part of a phone line's bandwidth not used for voice so as toallow simultaneous voice and data communication.

As a non-limiting example, in the case wherein the WLAN unit 30 is usingchannel 10 (shown as curve 25 in FIG. 2) centered around 2457 MHz, theconverter is required to shift the frequency up or down by 2457−19=2438MHz resulting in the frequency allocation shown in graph 40.

In order to avoid interference to and from the other signals (POTS 41and ADSL 42) carried over the same telephone pair, a High Pass Filter(HPF) 32 is connected between the converter 31 and the telephone wiringconnector 36. The telephone wiring connector 36 in commonly a telephonestandard RJ-11 plug used in North America, allowing for coupling theOFDM modem 30 to the telephone pair. The HPF 32 may use passivecomponents implementing a Butterworth filter scheme. In some cases, atelephone unit is required to share the same telephone wiring connector35. In such a case, a Low Pass Filter (LPF) 34 is used to isolate thePOTS frequency band, allowing a telephone set to couple to the telephoneconnector 35 via a telephone jack (e.g. RJ-11 jack). Any common filterused to isolate POTS and ADSL signals (a.k.a. micro-filter) may be usedas LPF 34, comprising discrete capacitors and inductors). Suchconfiguration of connecting modem and telephone via a set of LPF and HPFunits is known in the art and commonly used also in HomePNA environment.

OFDM and other spread spectrum modulation techniques are known to bepowerful, robust and high-performance. Yet, their implementationcomplexity and associated costs have militated against their use incommunication systems. Even the first WLAN technologies introduced usedsingle-carrier technologies, such as IEEE802.11b using CCK. As such, theOFDM modem 30 shown in FIG. 3 may be used as a superior substitute tothe prior art HomePNA based phonelines communication. Since the powerfulOFDM technology is used, the modem performance is expected to exceed anyavailable or future HomePNA technology using single carrier modulation(such as QAM) as known in the prior-art. Furthermore, since the modemutilizes existing off-the-shelf wireless oriented components such as thewireless MAC 13 b, the baseband processor 18 and the RF-IF converter 16,the required effort to develop a dedicated modem is obviated.Furthermore, the rapid proliferation of the WLAN solutions to theresidential, office, enterprise and industrial applications, a trendexpected to even grow in the future, indicates a high volume of WLANcomponents, resulting in easy availability, low price and ensuredinteroperability.

Up/Down converter 31 used for shifting the frequency as described aboveis well known in the art. Such converters are known to use mixing andfiltering techniques, and may use single or multiple stages(Superheterodyne scheme) as well as Direct Conversion (DC) architecture.A non-limiting example for Up/Down Converter function block 37, shown inFIG. 3 to include the functions of the converter unit 31, the RF filter21 and TX/RX Switch 19, is shown as block 50 in FIG. 5. Such a block 50shifts the frequency of the RF signal coupled to port 51 to a lowfrequency (IF) signal in port 68. RF Signal received in port 51 isshifted down by a down channel based on mixer 57 a and Band Pass Filter(BPF) 58 a and is outputted at port 68. Similarly, an IF signal receivedin port 68 is shifted to the RF band by the up channel comprising mixer57 b and BPF 58 b, and as RF signal outputted via port 51. The RF port51 is coupled to the HPF 32 of the OFDM modem 30 and the IF port 68 iscoupled to the RF-IF converter 16 of the OFDM modem 30.

While transmitting to the telephone pair via connector 36, a RF signalreceived in port 51 (from the RF-IF converter 16) is first filtered bythe BPF 52 to remove any unwanted signals residing outside the frequencyband of the RF channel (e.g. the ISM RF channel band). Since theconverter 50 allows conversion in only one direction at a time, eitherup or down, ganged switches 56 a and 56 b are used, having a center polemarked as (1) and two throw states marked as (2) and (3). Whenconverting from RF to IF, both switches 56 a and 56 b are in the (2)state, hence the down channel is operative. Such a switch may be basedon PIN diode as explained above regarding switch 19. The RF signal fromthe RF port 51 couples to mixer 57 a via BPF 52 and switch 56 a. Themixer 57 a multiplies the local oscillator 54 sine wave signal providedto its LO port via a splitter 55 by the RF signal coupled to its RF port(using its non linear characteristics), yielding in its IF port a signalhaving two main components, one around the sum of the frequencies andone around their difference. The frequencies' sum signal is thenfiltered out by the BPF 58 a, and fed to the IF port 68 via the switch56 b. A driver 59 may also be included in order to allow proper drivingof the load connected to port 68. In a similar way, when receiving fromthe telephone pair, an IF signal from port 68 (originated in thetelephone pair, and coupled via connector 36 and HPF 32), is routed viathe switch 56 b (now in state (3)) to the IF port of mixer 57 b, via BPF58 b. A signal is also fed from the local oscillator 54 via splitter 55to the LO port of the mixer 57 b, which outputs an RF signal to port 51via the switch 56 a (now in state (3)) and BPF 52. A level detector (orcomparator) 53 is used to monitor the level of the revived RF signal,and accordingly operate the switches 56 a and 56 b via control channels69 b and 69 a respectively.

The converter 50 has been described above as having dedicated up anddown channels. However, since only one channel is used at a time and thetwo channels are not used simultaneously, a single channel (mixer) mayalso be used, wherein an appropriate switching mechanism is employed.

A level detector 53 may be designed based on LM311 Voltage Comparatoravailable from National Semiconductors headquartered in Santa-Clara,Calif. U.S.A. The local oscillator 54 may be based on quartz crystaloscillator, wherein the frequency is multiplied using Phase Locked Loop(PLL) circuits, and may comprise T83027 PLL Clock Generator IC with VCXOavailable from TLSI Incorporated of Huntington, N.Y. U.S.A., whose datasheet is incorporated herein by reference. A mixer 57 may be designedbased on MAX9993 High Linearity 1700 MHz Down-Conversion Mixer with LOBuffer/Switch available from Maxim Integrated Products of Sunnyvale,Calif. U.S.A, whose data sheet is incorporated herein by reference. Itshould be noted that other techniques and methods to implement theconverter block 50 functionality are known in the art and may be equallyused. Typically, converter block 50 may connect to the telephone wiringusing line interface functionalities such as isolation, impedancematching, driving/receiving and filtering, as will be described belowfor line interface 76 shown in FIG. 6.

The OFDM modem 30 inherently employs double frequency conversions: fromIF to RF by converter 16 and back to low frequency by converter 31. Thisredundancy may be obviated by directly extracting the baseband signalwithout going through the RF stage, as shown in OFDM modem functionalblock diagram 60 illustrated in FIG. 6, which may be used in one or moreembodiments of the present invention.

Similar to modem 30, modem 60 is based on WLAN unit 10 described inFIG. 1. However, the OFDM baseband signal generated by the broadbandprocessor 18 is not frequency shifted to RF, but rather handled directlyin the IF spectrum. In one non-limiting example, the baseband processor18 provides an orthogonal analog I/Q signal pair. In this case, a lineinterface 76 using a Quadrature Modulator/Demodulator 191 shown in FIG.6 a converts the signals directly to a baseband analog signal centeredaround 19 MHz (for example by using 19 MHz local oscillator) in theexample of spectrum allocation according to graph 40. In anotherexample, an analog signal centered around another frequency is output bythe WLAN components comprising baseband processor 18, and in such a casea simple and single frequency conversion may be used in order to centerthe signal around 19 MHz.

A functional block diagram of the line interface 76 is shown in FIG. 6a. The line interface 76 couples to the I-Q modulator 15 in the basebandprocessor 18 via port 192. The I-Q signals are converted into a singlereal signal centered around the 19 MHz frequency (shifted from zero) bythe Quadrature Modulator/Demodulator 191, which may be based on MaximMAX2450 3V, Ultra-Low-Power Quadrature Modulator/Demodulator from MaximIntegrated Products of Sunnyvale, Calif. U.S.A, whose data sheet whichis incorporated herein by reference. The Modulator/Demodulator outputimpedance is 75 ohms terminated by a resistor 190 (if required), and fedto a driver 186 via BPF 188 a, passing only the required band (e.g. band43 in graph 40). An analog switch 183 routes the transmitted signal tothe telephone wiring (via port 36 and HPF 32) via an isolation unit 182and through port 181. The isolation unit 182 is typically based on asignal transformer 193, and serves to reduce common-mode noises so as toprovide a balanced signal, as well as meeting the required safety andESD requirements imposed by the UL in the U.S.A. and CE in Europe.

Similarly, a signal received from the telephone wiring is isolated bythe isolation unit 182, and routed via the analog switch 183 to an AGC187. A 100 Ohm resistor 185 serves as a termination, matching thetelephone wiring characteristic impedance to avoid reflection. Afterbeing filtered by a BPF 188 b, the signal is I-Q modulated by themodulator 191 and coupled to the baseband processor 18.

A sample network 75 over a telephone line using OFDM modems is shown inFIG. 6 b. A telephone wiring infrastructure as commonly exists inresidences in North America is described, based on single telephone pair62 accessed via outlets 63. A daisy-chain configuration is shown,wherein wiring segment 62 d connects outlets 63 d and 63 c, wiringsegment 62 c connects outlets 63 b and 63 c and wiring segment 62 bconnects outlets 63 a and 63 b. Wiring segment 62 a connects the ‘first’outlet 63 a to the PSTN (Public Switched Telephone Network) 61 via ajunction box (not shown) and the external wiring part known as ‘localloop’ or ‘subscriber loop’. In each outlet, a standard telephone RJ-11jack is connected to the wiring 62, allowing telephone units to beconnected thereto, using RJ-11 plug. Outlets 63 a, 63 b, 63 c and 63 drespectively comprise jacks 64 a, 64 b, 64 c and 64 d. Other wiringtopologies such as ‘star’ (a.k.a. ‘HomeRun’, ‘structured wiring’), treeand mixed topologies are also available, and are also suitable.

OFDM Modems 30 and 60 may be connected to and networked over thetelephone wiring 62 by connecting to the respective RJ-11 telephoneconnector 64 in outlet 63, and via cable 74 to the OFDM modem connector36, marked as ‘wiring’ connection. A network may include only OFDMmodems 30 as shown functionally in FIG. 3, or only OFDM modems 60 asshown functionally in FIG. 6 or any combination thereof. The network 75is shown to include an OFDM modem 30 b connected by a cable 74 d tooutlet 63 d, an OFDM modem 60 a connected by a cable 74 b to outlet 63 band OFDM modem 30 a connected by a cable 74 a to outlet 63 a. In eachcase, connection to the outlets is via the respective connectors 64 d,64 b and 64 a. Computer 66 a is shown connected to the OFDM modem 30 bvia its ‘data’ port (representing port 33 in FIG. 3), and computer 66 bis connected to OFDM modem 60 a via its ‘data’ port (representing port33 in FIG. 6). The computers 66 represent any data units, preferablyconnected via a standard wired data interface. The modems 30 a and 60 aallow a half duplex communication between the computers 66 a and 66 bover the telephone wiring. Similarly, additional OFDM modem 30 a mayalso support an additional data unit through its ‘data’ port.

Simultaneously with the data network formed over the telephone line, thestandard telephone service is also provided. Telephone set 65 a isconnected to the wiring 62 (so as to connect to the PSTN 61) via the‘TEL.’ Port (port 35 in FIG. 3). Similarly, telephone sets 65 c and 65 dconnect to the PSTN 61 (via the respective outlets 63 and wiring 62) byconnecting to OFDM modems 60 a and 30 a, respectively. Telephone set 65b is directly connected to outlet 63 c (via cable 74 c and plug/jack 64c). In such a case, the usage of LPF 34 (a.k.a. micro-filter) isrecommended in order to avoid interference to and from the other signalsusing the same telephone wiring as a medium.

In order to enable the computers 66 a and 66 b to connect to an externalnetwork (such as the Internet), a device connected to the externalnetwork (either broadband or narrowband) is commonly employed,non-limiting examples including a DOCSIS based cable modem, an ADSLmodem, wireless (such as WiMax) and others. Such a device should beconnected to the ‘data’ port of any OFDM modem, hence allowing sharingthe external connection to data units connected throughout the building.In one example, an ADSL modem 67 is used. The ADSL modem is shown toconnect to the telephone outlet 63 a via cable 74 e for coupling to theADSL signal 42 (depicted in FIG. 4), and providing a standard datainterface (e.g. USB, 10/100BaseT). This data interface in turn connectsto the OFDM modem 30 a ‘data’ port, thus allowing computers 66 a and 66b to share the ADSL connection via the formed network. The OFDM modem 30a is likewise connected to the telephone outlet 63 a via a cable 74 a(together with cable 74 e).

While network 75 has been described with regard to ‘bus’ topologywherein all the modems are connected to the same medium (telephonewiring 62), it is known that better communication performance (e.g.data-rate) may be achieved in point-to-point structure, wherein twomodems are connected at the ends of a wiring segment. Such configurationmay exist in newly installed infrastructures (e.g. structured wiring ina newly constructed building) or in MDU (Multiple Dwelling Unit), MTU(Multiple Tenant Unit) and MHU (Multiple Hospitality Unit). In all theabove, the wiring segments are in ‘star’ topology, wherein each wiringsegment connects a remote site (e.g. apartment) to a center (e.g.basement).

An application of OFDM modems to such topology is shown as anon-limiting example as network 70 in FIG. 7. The infrastructure ofnetwork 70 is described as comprising two wiring segments (eachcomprising a single pair) 72 a and 72 b, respectively connected betweenconnection points 73 a and 73 b (e.g. in junction box) and respectiveoutlets 63 a and 63 b, allowing telephone connection via the respectiveconnectors 64 a and 64 b. In order to allow both telephone and datasignals over the same wire pair, OFDM modems (either modem 30 or modem60 types) are connected to each wiring end. OFDM modem 60 a connects towiring segment 72 a via outlet 63 a, communicating over the wiringsegment 72 a with OFDM modem 30 a connected to the other end of thewiring segment 72 a via connection point 73 a. Telephone signals arecarried over the lower band, allowing telephone set 65 a to connect toPSTN 61, simultaneously with the OFDM signal carried over a distinctband and connecting the computer 66 a (representing any data unit) tothe Internet 71 (via any connection such as ADSL DOCSIS cable modem orwireless). Similarly, OFDM modem 30 c connects to wiring segment 72 bvia outlet 63 b, communicating over this pair with OFDM modem 30 bconnected to the other end via connection point 73 b. Telephone signalsare carried over the lower band, allowing telephone set 65 b to connectto PSTN 61, simultaneously with the OFDM signal carried over a distinctband and connecting the computer 66 b (representing any data unit) tothe Internet 71 (via any connection such as ADSL DOCSIS cable modem orwireless).

Outlet Enclosed Modem.

Outlets in general (to include LAN structured wiring, electrical poweroutlets, telephone outlets, and cable television outlets) havetraditionally evolved as passive devices being part of the wiring systemhouse infrastructure and solely serving the purpose of providing accessto the in-wall wiring. However, there is a trend towards embeddingactive circuitry in the outlet in order to use them as part of thehome/office network, and typically to provide a standard datacommunication interface. In most cases, the circuits added serve thepurpose of adding data interface connectivity to the outlet, added toits basic passive connectivity function.

An outlet supporting both telephony and data interfaces for use withtelephone wiring is disclosed in U.S. Pat. No. 6,549,616 entitled‘Telephone outlet for implementing a local area network over telephonelines and a local area network using such outlets’ to Binder. Suchoutlets are available as part of NetHome™ system from SercoNet Inc. ofSouthborough, Mass. U.S.A.

Another telephone outlet is described in U.S. Pat. No. 6,216,160 toDichter, entitled ‘Automatically configurable computer network’. Anexample of home networking over CATV coaxial cables using outlets isdescribed in US Patent Application 2002/0194383 to Cohen et al.entitled: ‘Cableran Networking over Coaxial Cables’ to Cohen et al. Suchoutlets are available as part of HomeRAN™ system from TMT Ltd. ofJerusalem, Israel. Outlets for use in conjunction with wiring carryingtelephony, data and entertainment signals are disclosed in US PatentApplication 2003/0099228 to Alcock entitled ‘Local area and multimedianetwork using radio frequency and coaxial cable’. Outlets for use withcombined data and power using powerlines are described in US PatentApplication 2003/0062990 to Schaeffer et al. entitled ‘Powerline bridgeapparatus’. Such power outlets are available as part of PlugLAN™ byAsoka USA Corporation of San Carlos, Calif. USA.

While the active outlets have been described above with regard tonetworks formed over wiring used for basic services (e.g. telephone,CATV and power), it will be appreciated that the invention can beequally applied to outlets used in networks using dedicated wiring. Insuch a case, the outlet circuitry is used to provide additionalinterfaces to an outlet, beyond the basic service of single dataconnectivity interface. As a non-limiting example, it may be used toprovide multiple data interfaces wherein the wiring supports single suchdata connection. An example of such outlet is the Network Jack™ productfamily manufactured by 3Com™ of Santa-Clara, Calif., U.S.A. In addition,such outlets are described in U.S. Pat. No. 6,108,331 to Thompsonentitled ‘Single Medium Wiring Scheme for Multiple Signal Distributionin Building and Access Port Therefor’ as well as U.S. Patent Application2003/0112965 Published Jun. 19, 2003 to McNamara et al. entitled ‘ActiveWall Outlet’.

While the outlets described above use active circuitry for splitting thedata and service signals, passive implementations are also available. Anexample of such passive outlet is disclosed in WO 02/25920 to Binderentitled ‘Telephone communication system and method over local areanetwork wiring’. Such outlets are available as part of the etherSPLIT™system from QLynk Communication Inc. of College Station, Tex. USA.

As known in the art, from the data communication (high frequency band)point of view, the cables 74 connected to the outlets 63 in system 75are known as ‘taps’. Cable 74 c, terminated in the LPF 34 is consideredan ‘open tap’ or ‘bridged tap’. The same goes for cable 74 e,terminating the ADSL band, but open for higher frequencies. Cable 74 b(as a non-limiting example) is considered a ‘terminated tap’, sinceappropriate termination is expected to be part of the OFDM modem 60 a.Taps in general and non-terminated taps in particular, are considered amajor impairment in any wired communication system. Reflections aregenerated at the tap points and at the ends of open taps, resulting in a‘notch’ pattern in the appropriate frequency. Such characteristicsrender part of the spectrum non-usable. As such, taps results in lowercommunication performance, and it is therefore desirable to eliminatetaps as much as practical.

Wireless system in general, and WLAN systems in particular areassociated with mobile and handheld devices such as PDA (PersonalDigital Assistant), cellular phone, remote-controller and laptopcomputers. Being mobile and man-carried, the space and weight of thewireless components is critical. As such, a lot of resources areallocated to integration and miniaturization efforts in order to makethe wireless components as small as possible. Vendors are increasinglyfocusing on integrating more and more functions into a minimum set ofchips and peripherals. Hence, the small dimension featured by thewireless components makes them well suitable to be housed within smallenclosures such as outlets.

In one or more embodiments of the present invention, the OFDM modem(partially or completely) is integrated into a telephone outlet. Inaddition to providing all the advantages described in the aforementionedprior art, such configuration eliminates the tap related impairments,thus improving the communication performance. As a non-limiting example,in the case the OFDM modem functionality is integrated into outlet 63 d,the cable 74 d is effectively zero in length, hence effectivelyeliminating the tap existence.

A pictorial view of such outlet integrating OFDM modem functionality isshown as outlet 80 in FIG. 8. The telephone wiring connector 36 is inthe back of the outlet (facing the wall), for connecting to the wiringin the common way of connecting wiring to a telephone outlet. The outlet80 front (facing the room) comprises connector 33, shown as RJ-45 for10/100BaseT interface. A telephone connector 35 a is shown as standardtelephone connector RJ-11 jack. A second connector 35 b may also be usedfor allowing connection to multiple telephone sets. The outlet 80 alsocomprises indicators 81 a and 81 b (LEDs) that may be used to indicateproper operation such as power availability, communication status (suchas LINK signal in Ethernet systems), communication performance andothers.

The above-described outlet 80 is a complete and self-contained device.As such, it can be easily installed in new houses instead of regularpassive simple outlets. However, such solutions are not appropriate inthe case of retrofitting existing wiring systems. In most cases, anysuch modification will require dismantling the existing outlets andinstalling the new ones having the improved features. Such activity iscumbersome, expensive and will often require professional skill.Furthermore, owing to safety aspects involved while handling hazardousvoltages (such as in the powerlines and telephone lines), localregulations may require only certified personnel to handle the wiring,making it expensive and militating against a do-it-yourself approach.

Furthermore, as technology and circumstances change in time, a need toupgrade, modify or change the outlet functionalities, features andcharacteristics may arise. For example, the data interface may need tobe upgraded to interconnect with new standards. In another example, thecircuitry may need to be upgraded to support higher bandwidth.Similarly, management and Quality of Service (QoS) functionalities mayneed to be either introduced or upgraded. In yet another example,additional functionalities and interfaces may need to be added. Usingcomplete self-contained outlets as a substitute to the existing onesalso introduces the disadvantages described above.

One approach to adding functionality to existing outlets is by using aplug-in module. Such plug-in modules for use with powerlinecommunication are described in US Patent Application 2002/0039388 toSmart et al. entitled ‘High data-rate powerline network system andmethod’, US Patent Application 2002/0060617 to Walbeck et al. entitled‘Modular power line network adaptor’ and also in US Patent Application2003/0062990 to Schaeffer, JR et al. entitled ‘Powerline bridgeapparatus’. Such a module using HomePlug™ technology are available frommultiple sources such as part of PlugLink™ products by Asoka USACorporation of San Carlos, Calif., USA. However, such plug-in modulesare known only with regards to power outlets, and are not available fortelephone or CATV outlets.

A plug-in module according to one or more embodiments of the presentinvention is shown as module 90 in FIG. 9. The module 90 is based on theoutlet 80 described above. However, in contrast to being an outlet, themodule 90 has an RJ-11 plug that plugs in the RJ-11 jack 93 of thetelephone outlet 91, the latter thus not requiring replacement ormodification. In order to allow mechanical securing of the connection,the module 90 comprises two sliding sides 94 a and 94 b, which arelatched and pressed against the outlet 91 surfaces 92 a and 92 brespectively. In this way, the module 90 is both electrically connectedto the wiring and mechanically attached to outlet 91, while notrequiring any specific skills or tools. The POTS service is fullyretained through the telephone connectors 35 a and 35 b.

Wireless Port.

Both OFDM modems 30 and 60 described above offer two wired ports, namelythe data unit port 33 and the telephone wiring port 36, and function toconvert signals between those ports. Adding a wireless port will enablethe OFDM modems also to network with data units over a non-wired medium.

Such an OFDM modem 100 comprising an antenna 22 as a wireless port isshown in FIG. 10. Generally, such a modem 100 can be considered as acombination of a WLAN unit 10 and OFDM modem 30 respectively asdescribed above in relation to FIGS. 1 and 3. Modem 100 is shown toinclude the full WLAN unit 10 functions, and as such may function asWLAN unit 10. However, the RF signal is coupled in between the RF-IFconverter 16 and TX/RX Switch 19 by a sharing device 101. The RF signalis thus also coupled to the telephone wiring connector 36 via theUp/Down Converter 31 and the HPF 32, similar to the description aboverelating to OFDM modem 30. Similarly, a telephone set may be coupled viaconnector 35 and LPF 34.

The sharing device 101 is a three ports device and functions to sharethe three RF signals, such that an RF signal received in any one of theports is replicated and shared by the other two ports. One RF signalrelates to the wireless radio communication via the antenna 22, a secondsignal relates to the telephone wiring carried signal via connector 36and the third RF signal is associated with the data port 33.

In such a configuration, the OFDM modem 100 communicates via threeports: Wireless port via antenna 22, wired data unit port via connector33 and wired telephone wiring connector 36. A data packet (such asEthernet packet) received from the data unit connected via port 33 willbe converted to an OFDM RF signal at the RF-IF Converter 16 port, andthen fed via sharing device 101 to both the telephone wiring after beingdown converted to a baseband signal by the Up/Down Converter 31 andthrough HPF 32 (as described above for modem 30), and in parallel (viasharing device 101) to the antenna 22 to be transmitted over the air.Similarly, an OFDM RF signal received in the antenna 22 is fed via thesharing device 101 to both the telephone wiring port 36 in analogbaseband form and data unit port 33 as digital packets. Baseband signalsreceived via the telephone wiring port will be converted to RF and thentransmitted to the air by the antenna 22 in parallel to being downfrequency converted and encoded into a packet in digital form in port33. In some cases, an RF signal may be received from both the antenna 22and the telephone wiring (via port 36). Since wireless systems are ableto handle the through-air multi-path phenomenon, the signal received viathe telephone wiring channel should be appreciated as another signalpath, hence being handled by the baseband processor 18.

The three ports modem 100 is shown to share the three RF signals bysharing device 101. In one or more embodiments of the present invention,the sharing function is performed in the baseband (or IF) frequencyspectrum. Such a modem 105 is shown in FIG. 10 a. Similar to modem 100,three ports are supported, two wired and one wireless. However, incontrast to modem 100, the sharing device 106 shares three basebandsignals: an antenna 22 coupled signal, via the RF-IF Converter 16,telephone wiring signal via line interface 76 and data unit relatedsignal via the baseband processor 18. One advantage of suchconfiguration is the use of a single Up/Down Converter 16, rather thanthe two converters (16 and 31) used in modem 100 configuration.

Similar to the above discussion relating to OFDM modems 30 and 60,wireless-port equipped modems 100 and 105 may be equally enclosed withina telephone outlet or snap-on module. Such a snap-on module 110 attachedto a telephone outlet 91 is shown in FIG. 11. Module 110 is similar tomodule 90 shown in FIG. 9, but in contrast attaches to the outlet usingscrews 111 a and 111 b rather than by snap-fit connection. It should benoted that other mechanical attachment means could be equally employed.In addition to the wired ports shown for module 90, an antenna 22 isshown, serving as additional over-the-air wireless port.

A network 120 utilizing a wireless port equipped OFDM modem 100 is shownin FIG. 12. OFDM modem 105 may be equally employed. The network 120 isbased on network 75 shown in FIG. 6 b, wherein OFDM modem 100 asubstitutes OFDM modem 30 b, hence introducing a wireless port 22 a tothe network. Computer 66 a and telephone unit 65 a connect to the OFDMmodem 100 a in a similar manner as before. The additional port 22 aallows for a laptop computer 66 c to be connected to the wireless bridge121 a comprising an antenna 22 b. Similarly, the wireless clientfunctionality 121 a may be built in the computer 66 c. A wireless linkaccording to standard IEEE802.11g is established between the bridge 121a and the modem 100 a, hence enabling the computer 66 c to network withthe other data units connected to the telephone wiring 62, as well as tocomputer 66 a.

While a single modem 100 or 105 is part of network 120, it should beappreciated that multiple such modems may be used, each covering adifferent area in the premises, hence enlarging the actual wirelesscoverage. Furthermore, such network 120 offers the user the flexibilityof adding data units either through wiring (by connecting to the dataports of the OFDM modems) or wirelessly (via the wireless port).

In some cases, only wireless ports may be required, thus tethered dataunit connection may be obviated. According to one or more embodiments ofthe present invention, a wireless adaptor 130 supporting only wirelessport is shown in FIG. 13. The data unit port 33 associated functionsdescribed for modem 100 in FIG. 10 (such as baseband processor 18, MAClayer processor 13 and PHY 12) are omitted. The receiving path comprisesthe antenna 22, RF Filter 21 and TX/RX Switch 19. The received RF signalis then frequency down shifted by Up/Down converter 31, and fed to thetelephone wiring via connector 36 and HPF 32. Similarly, any OFDM signalcarried by the telephone wiring is received and up converted to RF, andthen feeds the antenna 22. A telephone set may be connected to thetelephone wiring via connector 35 and LPF 34.

A network 140 employing the wireless adaptor 130 is shown in FIG. 14.Wireless adaptors 130 a and 13 b are respectively connected to outlets63 d and 63 b, and respectively employ antennas 22 a and 22 c. Computer66 c is wirelessly coupled to the telephone wiring 62 via the wirelessbridge 121 a and antenna 22 b, communicating with adaptor 130 a via itsantenna 22 a. Similarly, computer 66 d is wirelessly coupled to thetelephone wiring 62 via the wireless bridge 121 b and antenna 22 d,communicating with adaptor 130 b via its antenna 22 c. In thisconfiguration, the computers 66 c and 66 d communicate over thetelephone wiring 62 via the respective adaptors 130. In such a system,the telephone wiring 62 and the adaptors 130 serve as a repeater, thusallowing communication between units, which cannot directly wirelesslycommunicate. The lower frequency band of the wiring is usedsimultaneously to carry telephone signals between the PSTN 61 and thetelephones 65 a, 65 b, 65 c and 65 d. Telephone sets 65 a and 65 crespectively connect via adaptors 130 a and 130 b. Telephone sets 65 band 65 d connect to the wiring 62 via LPFs 34 a and 34 b, respectively.

Antennas 22 b and 22 d may be sufficiently close to enable directwireless communication between bridges 121 a and 121 b. In such case, inaddition to the path (or multiple paths) formed through the air, atelephone wiring path is added. As a non-limiting example, bridge 22 dmay receive signals transmitted by bridge 121 a via the air. Inaddition, the transmitted signal is received by adaptor 130 a (viaantenna 22 a), and converted to baseband and carried over the telephonewiring segments 62 d and 62 c. The signal is then extracted by adaptor130 b, up frequency shifted and transmitted through the air via antenna22 c to the bridge 121 b, hence forming an additional path. Since mostwireless technologies and IEEE802.11g in particular are well equipped tohandle multi-path, this phenomenon is not expected to degrade thecommunication performance.

While the invention has been described with regard to ‘bus’ topologytelephone wiring, it will be appreciated that wireless-port equippedmodems and adaptors may equally be used in point to point topology,‘star’ topology or any combination thereof.

While the invention has been described with regard to a single specificchannel frequency shifted to a specific band for use over the telephonewiring, it will be appreciated that the invention equally applies to anychannel that can be used (as shown in graph 20) and may be located atany usable frequency band over the telephone wiring (not limited to theexample shown as curve 43 of graph 40). Furthermore, several productsare currently available using multiple channels in order to improve datarate performance, as well as using other techniques to improvethroughput such as compression. Such techniques are sometimes known as‘Turbo-G’, ‘Dynamic Turbo’, ‘Super G’ and other brands. Such a solutionmay be equally employed in one or more embodiments of the invention,using larger baseband signal bandwidth. Exemplary techniques to improveeffective data rate are described in Atheros Communication White Paperentitled “Super G Maximizing Wireless Performance”, which isincorporated herein by reference.

While the invention has been described with regard to modems andadaptors supporting telephone port 35, it will be appreciated that theinvention equally applies to the case wherein the telephone wiring isnot carrying a telephone (POTS) signal. In such a case, telephoneconnector 35, LPF 34 may be omitted, and HPF 32 may be omitted andbypassed. Furthermore, such configuration may apply to any type ofwiring dedicated for carrying the baseband signal, not limited totelephone wiring of any kind.

In one or more embodiments according to the present invention, otherutility wiring (not limited to telephone oriented wiring) is used,carrying a service signal. For example, powerlines may be used to carryboth the AC power signal and the OFDM signal according to one or moreembodiments according to the present invention. In such a case, the HPF32 should be substituted with HPF filtering out the low frequency band(i.e. 60 Hz in North America and 50 Hz in Europe) carrying the AC signaland its associated noises. Similarly, in the case wherein the modem isrequired also to provide AC power connection, the telephone connector 35should be substituted with a two or three prongs power jack suitable forconnecting powered appliances, and the telephone-oriented LPF 34 shouldbe substituted by a LPF passing the 50/60 Hz AC signal. Furthermore,similar to the above discussion about housing the modem within atelephone outlet and telephone outlet snap-on module, the powerline OFDMmodem may be equally enclosed within an AC power outlet and snap-onmodule respectively, with the warranted modifications.

In one or more embodiments according to the present invention, the OFDMbaseband signal is carried over CATV cabling, carrying a CATV servicesignal. In one or more embodiments, the baseband signal may be employedover a band not used for carrying CATV signals (e.g. over 750 MHz insome implementations). The CATV analog video channels are usuallycarried each occupying a 6 MHz wide band. In such a case, an allocationof four adjacent channels will result in a total bandwidth of 6*4=24MHz, which may contain the 22 MHz wide OFDM baseband signal. In suchcase, the Up/Down Converter 31 used should shift the band to theallocated bandwidth, for example by tuning the local oscillator 54frequency to the required value. Similarly, The HPF 32 should besubstituted with a BPF passing the allocated 24 MHz, and the LPF 34should be substituted with a BSP (Band Stop Filter) blocking the OFDMsignal and passing the CATV channels, to be coupled to via RF connector(BNC or F-Type) substituting for the telephone connector 35.

A non-limiting example of generalizing OFDM modem 30 to be used with anytype of utility wiring is shown as modem 150 in FIG. 15. Connector 151is connectable to appropriate utility wiring, and represents a dedicatedspecific applicable connector, such as telephone connector 36 (e.g.RJ-11 plug) in the case where the utility wiring is telephone wiring, oran RF connector in the case of CATV cabling and AC power plug in thecase of powerlines. Similarly, a service connector 152 represents theappropriate service signal connector such as telephone connector 35, RFconnector and AC power jack when used with telephone, CATV and AC powerwiring, respectively. Service/Data Splitter/Combiner 153 functions topass the service signal to the service connector 152, to couple the OFDMbaseband signal to the Up/Down Converter block 37 and to avoidinterference between both signals. In the case of telephony, thefunctionality of the Splitter/Combiner 153 is provided by the LPF 34 andHPF 32. Similarly, LPF and HPF are used in powerline applications, forcoupling/stopping the AC power signal. For use over CATV wiring, BPF(Band Pass Filter) and BSP (Band Stop Filter) are used as describedabove.

Powering.

In most of the embodiments according to the present invention, the OFDMmodems (or wireless adaptor) include active components (such as Up/Downconverter 31), and as such need to be powered. Three non-limitingpowering schemes are described hereinafter including local feeding,power over wiring and via the interface module. The powering schemesapply to the modem/adaptor being a stand-alone enclosure, housed withinan outlet, enclosed within a snap-on outlet module or as part of a dataunit.

Local Feeding.

In this implementation the module is connected to an external powersource for feeding its active components. A common small AC/DC convertermay be connected to the modem/adaptor via a dedicated power connection.

A power adaptor may be used in the modem/adaptor, for adapting theexternal power to the internal needs. Such an adaptor may includevoltage conversion (such as DC to DC converter) in order to adapt tospecific voltages required, protection circuits (such as fuse or currentlimiting), regulation and noise filtration, as well as otherfunctionality as known in the art.

Power Over Wiring.

In one or more embodiments according to the present invention, the OFDMmodem (or the wireless adaptor) is fed by power carried over the wiringto which the module is connected. The power may be carried overseparated conductors. In this case, the same wiring connector (such as36 or 151) may be used to connect to the power carrying conductors usingseparated pins. Alternatively, an additional power dedicated connectormay be used.

In one or more preferred embodiments, the power is carriedsimultaneously over the wiring carrying the data network signals and/orthe basic service signal. The implementation of such a mechanism istrivial when the basic service is AC power. In such a case the power isextracted from the AC power signal carried, commonly via AC/DC converterand LPF filter.

Similarly, a recent technique known as Power over Ethernet (PoE) (a.k.a.Power over LAN) and standardized under IEEE802.3af, also explained inU.S. Pat. No. 6,473,609 to Lehr et al. titled: “Structure CablingSystem”, describes a method to carry power over LAN wiring, using thephantom mechanism. Such technology, as well as others, may be used toprovide power to any of the modems/adaptors described above, in the casewhere appropriate cabling (such as CAT. 5) is used as the wired medium.As a non-limiting example, in the case of using a different spectrum forthe power signal, a filter should be used. In the case of phantom typeof feeding, two transformers are required as known in the art.

Recent techniques developed allow for carrying simultaneously power andbasic service (and data) over the same wiring infrastructure. U.S.patent publication 2002/0003873 to Rabenko et al. titled: “System andmethod for providing power over a home phone line network” teachescarrying AC power over telephone wiring carrying both telephony anddata, by using a part of the spectrum not used by the other signals.Such a technique may be used for powering a modem or adaptor accordingto the current invention. As a non-limiting example, AC power using asine wave power signal of 50 KHz may be used. As shown in graph 40, a 50KHz signal is in a non-allocated frequency band, and hence may be usedfor power distribution with minimum or no interference to the othersignals carried over the same telephone wire pair.

In most prior-art systems involving carrying a power over a non-powerdedicated wiring (e.g. powerlines), the amount of power that can becarried is limited either due to safety regulations and limitations,ensuring minimum interference with the other signals carried over thesame wires or due to the power dissipation in the wires. For example,power carried over telephone lines may not exceed 60VDC due to safetylimitations, and power carried over coaxial wiring (e.g. CATV) maydegrade its signal carrying characteristics.

Wireless system in general, and WLAN systems in particular areassociated with mobile and handheld devices such as PDA (PersonalDigital Assistant), cellular phone, remote-controller and laptopcomputers. Being battery operated, the power consumption of the wirelesscomponents is critical. As such, a lot of resources are allocated tomake the wireless components consume very low power, and the powerconsumption of any wireless components is considered as one of its mainfeatures. This approach is described for example in Texas InstrumentsWhite Paper entitled “Low Power Advantage of 802.11a/g vs. 802.11b”which is incorporated herein by reference. Hence, the low power featureof the wireless components makes them well suitable to be used in anypower over wiring scheme, and also in any non-local feeding scenarios.

An additional advantage of carrying power over the same wires carryingthe OFDM signal relates to the superior characteristics of the OFDMsignal. Known single carrier modulations use the whole spectrum for thewhole data rates (single ‘bin’ approach), and as such are greatlysusceptible to both white noise and single frequency noise. In contrast,OFDM uses multiple ‘bins’, each carrying part of the data, and hence isless impaired by either white or narrowband noise. Power supplies areknown to be noisy, and in particular at specific frequencies, such asharmonies of the PWM frequency (in the case of PWM based supply).Furthermore, the wires connecting the wired medium to the power supplyand to the loads also serve as antennas and receive noise from theenvironment. Since the OFDM is much more robust, the effects describedare less severe, allowing better performance, and obviating the need forcomplex and expensive filters.

Furthermore, since the networks described above are used to servewireless clients (STAs) which are battery operated and thus areoperative even in the case of power outage, carrying power over thewiring allows for continuing network operation in such a case. The poweris typically sourced from a central back-up power source (e.g.UPS—Uninterruptible Power Supply), and allows continuous operation ofthe network even in the case of power outage via the wiring medium.

A non-limiting example of an OFDM modem 160 capable of being power fedvia the telephone wiring is shown in FIG. 16. OFDM modem 160 includesmodem 30 (shown functionally in FIG. 3) and added power extraction andfeeding functionalities. OFDM modem 160 connects to the telephone wiringvia telephone connector 36, in a way similar to modem 30. A BPF 162,optimized to pass only the 50 KHz power signal, extracts the powersignal and feeds AC/DC Power Supply 161, which converts to various DClevels usually required by the OFDM modem 30, such as 5 and 3.3 VDC. Thenon-power related signals (telephony, ADSL and OFDM baseband) are passedthrough BSF (Band Stop Filter) 163 (which may implement 50 KHz notchfilter, for example) and to the wiring port of OFDM modem 30. The dataand telephone ports of the OFDM modem 30 shown as 33 and 35 in FIG. 3are represented as modem 160 data port 164 and telephone port 165,respectively. Hence, OFDM modem 160 implements all OFDM modem 30functions, added to the capability of being powered by a power signalcarried over the telephone wiring.

The BPF 162 and BSF 163 constitute the power/signal splitter/combiner166. In the case wherein the power is carried in any other way, thisfunction block 166 should be accordingly modified to split/combine thepower and other signals carried over the wiring.

A network 170 employing AC power over telephone wiring is shown in FIG.17, based on network 75 described above with reference to FIG. 6 b. OFDMmodems 30 b and 60 a of network 75 are respectively substituted withtelephone wiring AC powered modems 160 b and 160 a, including the samefunctionalities added to the capability of being powered via thetelephone lines. The 50 KHz power signal is fed into the wiring via the50 KHz AC power supply 171, coupled to the telephone wiring 62 viaconnector 64 c of outlet 63 c, through a BPF 162 to avoid interferencewith the other signals carried over the same wiring 62. OFDM modem 30 ais used connected to outlet 63 a, hence using local powering.

Powering Via Connected Appliance.

As explained above, several data interface standards also carry powerover the interface. As a non-limiting example, in the case where themodule is connected to USB host unit, the USB interface may feed themodule. The same applies when the data port 33 is an Ethernet portimplementing PoE technology as described above.

While the invention has been described with regard to a single powersource, it will be appreciated that the invention equally applies to thecase wherein multiple power sources are used either for redundancy orload sharing.

General.

While the invention has been described with regard to the configurationwherein OFDM signal is carried over telephone wiring (or any otherutility or dedicated wiring LAN), it will be appreciated that theinvention equally applies to any other spread spectrum signaling (usingeither DSSS or FHSS). As a non-limiting example, any multi-carriermodulation technique may be used such as DMT (Discrete MultiTone) andCDMA (Code Division Multiple Access). The term ‘OFDM modem’ used hereinis to be considered as an example only, and not as limited to solelyusing OFDM based signal.

While the invention has been exampled above with regard to usingstandard IEEE 802.11g technology, signals and components, it will beappreciated that the invention equally applies to any other wirelessbased technology, using either single or multi carrier signals forimplementing either spread spectrum or narrowband, using eitherunlicensed bands (such as ISM) or licensed spectrum. Such technology maybe part of the IEEE 802.11 (such as IEEE 802.11b or IEEE 802.11a), ETSIHiperLAN/2 or any technology used for WLAN, home networking or PAN(Personal Area Network). One non-limiting example is using IEEE 802.11bbased on CCK (Complementary Code Keying). Other non-limiting examplesare BlueTooth™, ZigBee, UWB and HomeRF™. Furthermore, WAN (Wide AreaNetwork) and other wireless technologies may be equally used, such ascellular technologies (e.g. GSM, GPRS, 2.5G, 3G, UMTS, DCS, PCS andCDMA) and Local Loop oriented technologies (WLL—Wireless Local Loop)such as WiMax, WCDMA and other Fixed Wireless technologies, includingmicrowave based. Similarly, satellite based technologies and componentsmay be equally used. While the technologies mentioned above are allstandards-based, proprietary and non-standards technologies may beequally used according to present invention. Furthermore, the inventionmay equally apply to using technologies and components used in non-radiobased through-the-air wireless systems such light (e.g. infrared) oraudio (e.g. ultrasonic) based communication systems.

While the invention has been described with regard to the configurationwherein a single wireless oriented signal is carried over the wiringmedium (such as utility or dedicated wiring LAN), it will be appreciatedthat the invention equally applies to the case wherein multiple suchsignal are carried using FDM. For example, additional IEEE802.11g signalmay be added to graph 40, occupying the frequency band of 32-54 Mb/s,hence not overlapping the signals shown. Furthermore, different suchsignals may be combined, and thus not limited to the same wirelessoriented signal.

While the invention has been described with regard to networks using thesame wireless technology (such as IEEE802.11g) by all modems connectedto the wired medium, it will be appreciated that the invention equallyapplies to other embodiments wherein different but interoperable signalsare employed.

While the invention has been described with regard to embodiments usinga complete wireless solution based on existing components, includingwireless MAC 13 b, baseband processor 18 and converter 16, it will beappreciated that the invention equally applies to other embodimentswherein one or more of theses components are used. As a non-limitingexample, the MAC 13 b may be substituted with a wired-dedicated MAC,still employing all physical layer components. Similarly, other physicallayer components may be used, still using the powerful wireless MAC 13b. Furthermore, while the wireless signal, either as baseband, IF or RFform, has been described as only being frequency shifted, additionalprocessing may also apply to the standard wireless signals andcomponents, such as amplitude/level handling such as amplification andattenuation and frequency handling such as filtering. Such processingmay be warranted in order to better adapt to the wired medium, improvereliability or reduce costs.

While the invention has been described with regard to wireless signalsand systems carrying digital data, it will be appreciated that theinvention equally applies to other embodiments wherein the wirelesssignals (and system) are used to carry analog signals. One non-limitingexample involves cordless telephony. Cordless telephones are known tocarry telephone (and control) signals over the air using ISM bands.Applying the invention allows for carrying the signals over any wiredmedium in general and over a utility wiring in particular. In the caseof carrying the signals over telephone wiring, the above advantages areapparent, such as enlarging the coverage. Furthermore, suchconfiguration may allow carrying multiple telephone signals over asingle telephone pair.

Those of skill in the art will understand that the various illustrativelogical blocks, modules and circuits described in connection with theembodiments disclosed herein may be implemented in any number of waysincluding electronic hardware, computer software, or combinations ofboth. The various illustrative components, blocks, modules and circuitshave been described generally in terms of their functionality. Whetherthe functionality is implemented as hardware or software depends uponthe particular application and design constraints imposed on the overallsystem Skilled artisans recognize the interchangeability of hardware andsoftware under these circumstances, and how best to implement thedescribed functionality for each particular application.

Although exemplary embodiments of the present invention have beendescribed, this should not be construed to limit the scope of theappended claims. Those skilled in the art will understand thatmodifications may be made to the described embodiments. Moreover, tothose skilled in the various arts, the invention itself herein willsuggest solutions to other tasks and adaptations for other applications.It is therefore desired that the present embodiments be considered inall respects as illustrative and not restrictive, reference being madeto the appended claims rather than the foregoing description to indicatethe scope of the invention.

PUBLIC NOTICE REGARDING THE SCOPE OF THE INVENTION AND CLAIMS

While the invention has been described in terms of preferred embodimentsand generally associated methods, the inventor contemplates thatalterations and permutations of the preferred embodiments and methodswill become apparent to those skilled in the art upon a reading of thespecification and a study of the drawings.

Accordingly, neither the above description of preferred exemplaryembodiments nor the abstract defines or constrains the invention.Rather, the issued claims variously define the invention. Each variationof the invention is limited only by the recited limitations of itsrespective claim, and equivalents thereof, without limitation by otherterms not present in the claim. In addition, aspects of the inventionare particularly pointed out in the claims using terminology that theinventor regards as having its broadest reasonable interpretation; morespecific interpretations of 35 U.S.C. section.112 (6) are only intendedin those instances where the term “means” is actually recited. The words“comprising,” “including,” and “having” are intended as open-endedterminology, with the same meaning as if the phrase “at least” wereappended after each instance thereof.

1. A system carrying concurrently a LAN signal in a LAN frequency bandand a radio frequency signal in a first intermediate frequency banddifferent from and non-interfering with, the LAN frequency band over LANwiring in a building, the system comprising: a first device and a seconddevice connected by the LAN wiring; the first device including a highpass filter, connected to the LAN wiring and passing only signals in thefirst intermediate frequency band to a first signal frequency converter,the first signal frequency converter converting the radio frequencysignal in the first intermediate frequency band received from the LANwiring to a radio frequency band signal for transmission through anantenna to a wireless terminal and converting a radio frequency bandsignal received though the antenna from the wireless terminal to a firstintermediate frequency band signal for transmission over the LAN wiring;the first device further including a low pass filter connected to theLAN wiring and passing signals in the LAN frequency band to a firstnetwork device connected to the first device; and the second deviceincluding a high pass filter, connected to the LAN wiring and a networkinterface adapted to the second device to an external network; whereinthe high pass filter passes only signals in the first intermediatefrequency band between a processor and the LAN wiring and the processorconverts the radio frequency signal in the first intermediate frequencyband received from the LAN wiring to a network signal and converts areceived network signal from the external network to a radio frequencysignal in the first intermediate frequency band signal for transmissionover the LAN wiring.
 2. The system according to claim 1 wherein the LANwiring carries a second radio frequency signal in a second intermediatefrequency band, different from and non-interfering with the LANfrequency band and the first intermediate frequency band; wherein thefirst device includes a second high pass filter, connected to the LANwiring and passing only signals in the second intermediate frequencyband to a third signal frequency converter, the third signal frequencyconverter converting the radio frequency signal in the secondintermediate frequency band received from the LAN wiring to a radiofrequency band signal for transmission through an antenna to a wirelessterminal and converting a radio frequency band signal received throughthe antenna from the wireless terminal to a second intermediatefrequency band signal for transmission over the LAN wiring; and whereinthe second device includes a second high pass filter, connected to theLAN wiring and passing only signals in the second intermediate frequencyband to a fourth signal frequency converter, the fourth signal frequencyconverter converting the radio frequency signal in the secondintermediate frequency band received from the LAN wiring to the radiofrequency band signal for transmission through an antenna and convertinga radio frequency band signal received from the antenna to a secondintermediate frequency band signal for transmission over the LAN wiring.3. The system according to claim 1 wherein the first device furtherincludes a Tx/Rx switch connected between the antenna and the firstsignal frequency converter.
 4. The system according to claim 1 whereinthe first device further includes a radio frequency filter connectedbetween the antenna and the first signal frequency converter.
 5. Thesystem according to claim 1 wherein the second device further includesline interface connected between the high pass filter and the processor.6. The system according to claim 1 wherein the radio frequency bandsignal is a cellular telephone signal.
 7. The system according to claim6 wherein the cellular telephone signal is selected from the groupincluding GSM, GPRS, 2.5G, 3G, UMTS, DCS, PCS, CDMA, WCDMA and WiMAX. 8.The system according to claim 1 wherein the radio frequency band signalis a wireless local area networking signal.
 9. The system according toclaim 1 wherein the radio frequency band signal is a wireless wide areanetwork signal.
 10. The system according to claim 1 wherein the LANwiring carries a power signal and at least one of the first device andthe second device is powered by the power signal.
 11. The systemaccording to claim 1 wherein the second device further includes a lowpass filter connected to the LAN wiring and passing signals in the LANfrequency band to a second network device connected to the seconddevice.
 12. The system according to claim 1 wherein the second devicefurther includes a media access control layer processor connectedbetween the network interface and the processor.
 13. The systemaccording to claim 1 wherein the second device further includes: anRF-IF converter and a second signal frequency converter; the RF-IFconverter being connected between the second signal frequency converterand the processor for converting the radio frequency signal receivedfrom the second signal frequency converter to an intermediate frequencyband and converting an intermediate frequency band signal received fromthe processor to a radio frequency band signal; and the second signalfrequency converter connected between the RF-IF converter and the highpass filter for converting the radio frequency signal in the firstintermediate frequency band received from the high pass filter to aradio frequency signal and converting a radio frequency signal receivedfrom the RF-IF converter to a radio frequency signal in the firstintermediate frequency band signal for transmission over the LAN wiring.14. The system according to claim 13 wherein the second device furtherincludes a Tx/Rx switch connected between the RF-IF converter and thesecond signal frequency converter.
 15. The system according to claim 13wherein the second device further includes a radio frequency filterconnected between the RF-IF converter and the second signal frequencyconverter.
 16. The system according to claim 1 wherein the second devicefurther includes: a sharing device connecting the processor to the highpass filter and the an antenna; and an RF-IF converter connected betweenthe antenna and the processor for converting the radio frequency signalreceived from the antenna to an intermediate frequency band andconverting an intermediate frequency band signal received from theprocessor to a radio frequency band signal.
 17. The system according toclaim 16 wherein the first device further includes line interfaceconnected between the high pass filter and the sharing device.
 18. Thesystem according to claim 16 wherein the first device further includes aTx/Rx switch connected between the antenna and the RF-IF converter. 19.The system according to claim 16 wherein the first device furtherincludes a radio frequency filter connected between the antenna and theRF-IF converter.
 20. The system according to claim 1 wherein the seconddevice further includes: a sharing device connecting the processor tothe high pass filter and the an antenna; an RF-IF converter connectedbetween the sharing device and the processor for converting the radiofrequency signal received from the antenna to an intermediate frequencyband and converting an intermediate frequency band signal received fromthe processor to a radio frequency band signal; and second signalfrequency converter connected between the sharing device and the highpass filter for converting the radio frequency signal in the firstintermediate frequency band received from the high pass filter to aradio frequency signal and converting a radio frequency signal receivedfrom the sharing device to a radio frequency signal in the firstintermediate frequency band signal for transmission over the LAN wiring.21. The system according to claim 20 wherein the first device furtherincludes a Tx/Rx switch connected between the antenna and the sharingdevice.
 22. The system according to claim 20 wherein the first devicefurther includes a radio frequency filter connected between the antennaand the sharing device.